Fuel injection for internalcombustion engines



Nov. 17, 1953 G, M HOLLEY, JR 2,659,309

FUEL INJC'IION FOR INTERNAL-COMBUSTION ENGINES Filed Sept. 18, 1948 5 Sheets-Sheet l NOV. 17, 1953 G M HOLLEY, IR 2,659,309

FUEL INJECTION FOR INTERNAL-COMBUSTION ENGlNES Filed Sept. 18, 1948 3 Sheets-Sheet 2 OUT POQT L52, @E 5a Gi mf: il E H 5 kal/.152113 Jr.

IN V EN TOR.

NOV, 17, 1953 G, M- HOLLEY, 1R 2,659,309

FUEL INJECTION FOR INTERNAL-COMBUSTION ENGINES Filed Sept. 18, 1948 5 Sheets-Sheet 5 Patented Nov. 17, 1953 UNITED OFFICE FUEL INJECTION ooMUsTIo George M. Holley, Jij.,

Fon INTEHNAL- N ENGINES "Grsse reiste flinch. jas- `signr to George M. Holley and Earl Holley pplia'tll'sptelbet 18, 1948,861181 1Y0-'39,941 s claims. (o1. sql) Fig. 6 represents diagrammatically the 'opening and closing of dump Vport 58.

Fig. 7 represents dia ramniatically the cornposite 'motion of the niotions illustrated lin Figs. 3, '51, 5, land 6.

Fig. 8 shows a partial 'cross Ysection ltaken yon lplane 3 8 `of Fig. l. Fig. 9 shove/s an alternative simplified construction.

Fig. loshows diagrammatically the preferred method of injecting the fuel 'into the inlet inanifold of the engine.

In Figs. 1, 2 and 8, I0 is the fuel entrance leading out of the transfer pump I2, which vderives its fuel 'from the fuel reservoir I4.

I'S is the pipe delivering 'fuel from entrance I0 to the individual pump inlets II and I3 and from inlet n and so through H to port It, shown closed at the right of Fig. 1. l2Il is the shaft, plunger or piston rciprocated by the 'eccentric roller 22 mounted on the crank 'shaft 24 which carries an extension `25. shaft 24 is driven by a coupling 21 which is driven bythe engine.

The valve kseat of the port lI8 is formed between a shoulder I9 on the plunger, 'shaft or piston Y20 and the left hand end of the iloating piston 26, vvhich piston carries a pin A28.

A slot 30, in the shaft 20, extends on both sides of the pin 28 and allows a limited amount of relative motion between Din 28 and the Slot 3 0. By this means 'the plunger 20 and the vpiston 26 are loosely coupled together. The port I 8 is closed on the shoulder I9 before the pin 28 is even engaged by the left of the vslot 30.

A similar floating piston 32, a similar pin 34 and asimilar, although somewhat larger, slot 35 in th right hand end of plunger 20 extends to the right of the pin 3'4 which is similar to thema 2a.

The zitrein right hand end of :floating piston 32 ls shown covering the outlet port 38 in :the

The

. engine regulating the @gember .liingregsesf '.glpt. es. itxetates and. is recprocated determines stationarysleeveq. Fuel trapped in the end of the cylinder 42, before the left hand end jgf sleeve 3 2 closes port '38. is vdischargedthrough the pipe M jandhout of one of the ports I to one of the injection nozzles, not shown. '-I f ri angular port "48, in jmovable sleeve 50, regulates thetiine andainount of fuel injected intothe time and v amount of fuel rejected 'throug h outlet passage 200. A port 4 5 in 'tlie vstationary sleeve 43 is provided foreach one of the outl et passages 46. Each pf these ports 48 is timed-to releasethe pressure in the outlet 4B for a longer and longer period of time as the throttle 5I is closed and the suction The position of this wher` percentage of the fuel pumped 11e burnwn the engine and Vhow much is returned to the tank I4.. Opmng 5.2. in plunger 2.0 allows fueltrapped in cylinder 42, after port 38 is closed, 'to escape alon g 'tl`ie passag'e 5 4 in the center of plunger 2 0, through the 4escape port 58, back into inlet pipe VI6.

The slevefsn cirocates and rotates. Itis rotated by shaft gland its extension 25. 'lhe s1 v`e 5 0 is n i'o'vedup bypressure frointrnsier Pump y lz and is pun-ea :down by tensionsprmg so inside the forked rotating extension 25. A t a pered perforated valve 62 p'rovided with perforations 63 'allows f uel to escape fromchamber 1,2 'sd'e 'Sleeve '50-13; Chamber 64- .The Drle@- *tis Its-71, from 'the sleeve 5o, snee on thejtwo ball bearings liliy and 68 carried by thefforked extension 2 5. (See Fig. 8'.) This isa cloclrvvise "driving iean's, the ahutments y(i3 and `4I I having vertical faces 'which drive the rollers aI' 1`^d 68 yv vli'ich vare free to ris'e or fall Without disturbing 'the tini'g zof the V slts 48. The pressure in chanbr "N 'is maintained at atmospheric pressure. The 'fact that there is only a small resst'ane in the pipe connecting the outlet '29o with the top 'of the tank I4 and the fact that 'this tank I4 is open to the atmosphere cause this to he true. Valve B2 iis yrnoied down by diaphragm II).

' 'I8 tends to open -valve 62 and to 'compress the 'spring 16, slxpporting the valve B2. AThe spring 30 pulls the sleeve 50 down. A valve cage 65 (in which the valve 62 slides) is carried 'down by the downward niotio'n "01', lthe sleevev 50. The compression springs 16 and 18 :hold the valve 'si and -cause it to remain 'stenenar'y and thus valve sa tends to Aclose the ing between space 64 and space 5I the valve cage 65 is drawn down. Manifold air suction is applied to chamber 14, located above the diaphragm 10, through the passage 11. This suction acts against the spring 18. 16 is the spring holding the valve 62 up against the diaphragm 10. Fuel pressure in chamber 12 tends to open the valve 62. Spring 60 tends to close the valve 62. The upward movement of the diaphragm 10 is checked by the adjustable stop 19.

The action of the valve 62 is that of a servomotor valve and whenever valve 62 rises the sleeve valve 50 follows so as to make the eilective pressure in the chamber 12, inside the sleeve 50, equal the tension spring 60. When the valve 62 falls the pressure in chamber 12 falls and the spring 60 pulls valve 50 down to restore equilibrium. A restricted jet 80 is provided to make this servomotor mechanism work in the manner characteristic of all servovalves now in general use. That is to say, the restriction 80 increases as increase in flow through this restriction 80 increases. An increase in fiow through this restriction 80 follows the opening of valve ports 63. Valve 62 and ports 63 constitute the servovalve. The pressure in the chamber is balanced at all times against the pressure above the bridge in chamber 64 (which is a low pressure) and by the tension of the spring 60. When the valve 62 is pushed down by the upper compression spring 18, the pressure in chamber 5| falls (as valve 62 opens) so that the sleeve 50 descends to restore equilibrium; hence, there is a true servo-motor action and the sleeve 50 moves in response to variations of pressure in chamber 14.

In Fig. 3 AB represents the travel of one of the plungers 20. The complete circle represents one complete rotation of crank shaft 24 (360), A to B to A. The piston, to the right of Fig. 1, is shown at B.

In Fig. 4 the inlet port I8 is open from angular position (of 24) C to B and again from D to A. The gap B to D in Fig. 4 represents the travel from the piston 20, to the left, until it engages the pin 28, that is, the distance between the right hand face of the pin 28 and the right hand face of the slot 30. The piston 20 then picks up the piston 26 and D A represents the stroke of the piston 28 when the cylinder 42 is being filled with fuel. The gap A C, which equals the gap B D, represents the travel of the piston 20 before it picks up the piston 26 and closes the port I8 when injection begins.

In Fig. 5 the outlet port 38 is closed from angular position (cf 24) E to B and from F to A. The travel from B F corresponds to the gap 36 during which travel the port 38 remains closed. During the stroke from F to A pressure in the pipe 44 is made equal to the pressure in the chamber 42. During the travel from A to C (Fig. 4) port I8 gradually closes. During the travel from C to E fuel is ejected from chamber 42.

In Fig. 6 the dump port 58 is opened at the instant the out port 38 is closed. The angular position (of 24) G indicates the opening of port 58. The angular position (of 24) H indicates the closure of port 58.

In Fig. 7 the Figs. 3, 4, 5, and 6 have been combined so that the fuel is injected along pipe 44 between angular positions (of 24) C and G and fuel is drawn in from pipe I6 between positions H and F.

In Fig. 9, |00 is a shaft corresponding to shaft 20 of Fig. l.

Flange |02 corresponds to pin 28 of Fig. 1.

Annular piston |04 corresponds to piston 26 of Fig. 1.

Perforated disc |06, mounted on shaft |00, engages with the right hand of the annular piston |04. A soft metal sealing ring |03 is shown forming the left hand face of the loose piston |04.

When the shaft |00 has completed its stroke (operative pressure stroke) to the right, the right hand end of |00 engages with the left hand end of valve ||0 and compresses the compression spring ||4. Fuel caught in chamber |08 then escapes through the pipe |20, which is connected to the entrance I6 or to the tank I4.

Prior to the unseating of valve I I0 fuel escapes past the non-return valve |38 (sealed by the spring |40), through the passage 44 as before.

In Fig. 10 the pipe connected to the opening 46 of Fig. 1 is connected to a fuel nozzle 41, mounted in the inlet manifold 49. Throttle 5| controls the ow of air into the manifold 48. The pipe, connected to the opening 11 of Fig. i, is connected to the inlet manifold 49 at the opening 53. Air inlet valve 55 is shown adjacent to the fuel inlet nozzle 41.

Operation In Figs. 1, 2 and 8 assume the eccentric roller 22 is 180 from the position in -Which it is shown, then the port |8-I9 is open and the port 38 is closed and fuel fills the chamber 42 and pipe 44. After the eccentric roller 22 has been rotated about 45 the port |8-I9 is closed and fuel is pushed along the pipe 44 to the injectors.

As the sleeve 50 rotates the port 4S allows fuel to escape into the chamber 64. The location of the sleeve 50 determines for how many degrees rotation the port 48 is effective. The greater' the suction in chamber 14 the more the valve 62 rises, the more the sleeve 50 rises carrying with it the port 48 and the more fuel escapes through the port 45 in the stationary sleeve 43 and so through the outlet passage 200 thus reducing the fuel available for injection into the engine. The port 48 is shaped to close later and later as the suction in 14 increases as the shaft 24, Fig. 2, continues to turn so that eventually the plunger 20 reaches dead center and the motion of the pump is reversed. On the return stroke, the port 58 is closed immediately and port 38 remains closed because of the width of the slot 36 in the plunger 20. This prevents any suction forming in the pipe 44. The moment the 1notion reverses then the port |8-I9 is opened and remains open. When the pin 28, by remaining stationary, engages with the right hand end of slot 30, valve 26 travels to the left creating a suction in chamber 42 which draws in fuel. When plunger 20 almost reaches the end of its motion to the left, the pin 34 is engaged by the right hand end of slot 36 in the plunger 20. This results in the port 38 being opened and the cycle 1s repeated as the shaft 20 reverses and moves to the right.

Operation of Fig. 9

attacca valve H is unseated is determined 'by the -a'il- ;iustable valve housing H6, contained in the flanged valve housing |v| 8.

A cap |22 prevents leakage around lthe threads inside the valve housing I6.

When the shaft travels to y the left under the influence of the spring the perforated ldisc |06 picks up the vfree piston |04 and fuel flows into chamber |08 from chamber |01 `through fthe perforated disc |06, and the cycle is repeated.

It will be noted that the fuel is never .under a vacuum as the moment the plunger |00 reverses and moves to the left no appreciable drop in pressure can ever` exist in chamber |08. The moment this happens fuel flows from chamber |01, to the left of loose -piston |04, into chamber |08, The result is that no vapor is released and no vapor problem is created. The intent is to be able to pump ordinary gasoline without 'any vapor separator.

It will also be noticed that if the -fuel in the pipe 44 ever does contain vapor or air bubbles these 'bubbles will escape through the ports vin the rotary valve 48-50 as fuel is discharged frst through valve through nozzle 41.

The fuel returned through passage 2-00, to the tank I4, conveys the heat generated by the power required to pump, hence, the fuel is not overheated and for this additional reason there is no need of a vapor separator, The tank |4 is usually at atmospheric pressure.

Obviously Without departing from the teaching of my invention the element 50 may be held from rotation and merely reciprocated by the?" effect of manifold suction acting on the diaphragm 10. In that event the port 48 will open the port 45 at all times and there Will be a port similar to 48 for each of the pump units. -Each such port .48 and each such port 45 and their relation to each other must be held to close limits to get uniform distribution of fuel between the various cylinders. The uniformity of this distribution is the measure of success achieved 'by fuel injection devices as compared with ordinary' carburetors.

What I claim is:

l. A fuel injection pump and control therefor comprising a reciprocating rod, a cylinder, an annular free piston slidably mounted in said cylincler and surrounding said rod and spaced apart therefrom, a disc extending from and carried by said rod and engaging with the inner end of said piston so as to close the central opening in the piston during its pumping stroke and to open the said central opening during the suction operation of said pump, a passage to deliver fuel under pressure from said cylinder, pressure release means engaged by the outer end of said rod towards the end of its pumping stroke to check the discharge of fuel, a second one way connection from said rod to said piston adapted to engage with the other end of said annular free piston so as to leave the middle of the piston free to permit fuel to freely flow therein during its suction stroke, a rotating release valve said rotating release valve consisting of a rotating cylindrical drum, a formed port in the Wall of said drum an outlet from said fuel pump, a sationary escape port located in the outlet from said fuel pump and aligned with said formed port, the rotation of said drum being to timed that fuel is not delivered until said formed port has moved out of alignment with said escape port.

2. A fuel injection system, an air inlet manifold,

48 and immediately 'thereafterf 6 a thrcttleinitheinlet to said manifold, a source 4c! .'fuel'underpressure,

a metering pump cpmprisinga cylindrical pump chamber, -a fuel entrance 'there- Avto, la flanged plungerreciprocating thereinfaloose piston Aspaced 'apart from said plunger and lslidably kmounted inand closely fitting said cylinder Vandengaged by said flange on the pumping stroke of said plunger, an element projecting laterally from said plunger and located on lthe other 'side of said piston so as 4to 'engage therewith on the vsuction stroke of said plunger after a certain travel of said plunger, a discharge voutlet delivering fuel to the air inlet manifold, a relief port 'in 'said cylinder, a valve Vto close said port and 'means 4associated kwith said jplunger to open said port when the plunger approaches'the end of its vpump- 'ing stroke, and in which there is an escape port located in the outlet from said fuel pump, 'an escape yvalve loca-ted adjacentsaid escape lport and rin which there is also an 'air chamber, a moving wall forming one wall of said air chamber, a

` passage from said Aair chamber to the suction side of the throttle controlled air entrance, yieldable means acting-on said moving wall to oppose lthe -movement in response to said suction in the 4air entrance and mechanism connecting said escape valve with said vmoving wall.

3. A fuel injection pump and control therefor comprising a reciprocating rod, 'a cylinder, Aan annular free piston slidably mounted in 'said cylinder and surrounding 'said rod and spaced apart therefrom, a disc vextending from and carried by said rod and engaging with the inner end of said piston so as to close the central opening in the piston during its pumping stroke and to v'open the Isaid central opening during the suction operation of said pump, a passage to deliver fuel under pressure from said cylinder, pressure release means engaged by the outer end of said rod towards the end of its pumping stroke to check the discharge of fuel, a second rone Way Vconnection from said rod to said piston vadapted to engage with the other end of said annular free piston so as to vleave the middle of vthe piston free to permit fuel to freely ilow therein during its suction stroke, in which there is an air inlet manifold, a throttle in the inlet thereto, an escape port located in the outlet from said fuel pump, a release valve located adjacent said escape port and in which there is also an air chamber, a moving wall forming one wall of said air chamber, a passage from said air chamber to the suction side of the throttle controlled air entrance, yieldable means acting on said moving wall to oppose the movement in response to said variable suction downstream of said throttle and mechanism connecting said escape Valve with 'said moving Wall.

fi. A. fuel injection pump and control therefore comprising a reciprocating rod, a cylinder, an annular free piston slidably mounted in said cylinder and surrounding said rod and spaced apart therefrom, a disc extending from and carried by said rod and engaging with the inner end of said piston so as to close the central opening in the piston during its pumping stroke and to open the said central opening during the suction operation of said pump, a passage to deliver fuel under pressure from said cylinder pressure release means engaged by the outer end of said rod toward the end of its pumping stroke to check the discharge of fuel, a second one way connection from said rod to said piston adapted to engage with the other end of said annular free piston so as to leave the middle of the piston free to permit fuel to freely flow therein during its suction stroke and in which there is a rotating release valve consisting of a rotating cylindrical drum, a formed port in the wall of said drum, a stationary escape port located in the outlet from said fuel pump and aligned with said formed port, the rotation of said drum being so timed that fuel is not delivered until said formed port has moved out of alignment with said escape port, and in which there is also an air chamber, a moving wall forming one wall of said air chamber, a passage from said air chamber to a source oi variable pressure below atmospheric, yieldable means acting on said moving Wall and opposing the suction acting in said air chamber on said moving wall, said moving Wall being adapted to cause said rotating cylindrical drum to move axially with an increase in suction to restrict the fuel fed by said pump by allowing more fuel to escape through said formed port.

5. A fuel injection pump and control therefor, comprising a reciprocating rod, a cylinder, an annular free piston slidably mounted in said cylinder and surrounding said rod and spaced apart therefrom, a disc extending from and carried by said rod and engaging with the inner end of said piston so as to close the central opening in the piston during its pumping stroke and to open the said central opening during the suction operation of said pump, a passage to deliver fuel under pressure from said cylinder, pressure release means engaged by the outer end of said rod towards the end of its pumping stroke to check the discharge of fuel, a second one way connection from said rod to said piston adapted to engage with the other end of said annular free piston so as to leave the middle of the piston free to permit fuel to freely flow therein during its suction stroke and in which there is a rotating release valve consisting of a rotating cylindrical drum, a formed port in the Wall of said drum, a stationary escape port located in the outlet from said fuel pump and aligned with said formed port, the rotation of said drum being so timed that fuel is not delivered until said formed port has moved out of alignment with said escape port, and in which there is an air chamber, a moving Wall forming one wall of said chamber, a passage from said chamber to a source of variable pressure below atmospheric, yieldable means opposing the motion of said moving wall in response to the suction in said chamber, a pilot valve moved by said moving wall, a Wall at one end of said rotating drum, said pilot valve being slidably mounted in the center of said Wall, a cylinder closed at one end and having said rotating drum sliding in the other, means for admitting operating fluid under pressure to the inside of said cylinder to move said drum axially, yieldable means to oppose said movement, said pilot valve controlling the pressure inside said cylinder so that the drum follows the movement of said pilot valve and the formed port in the wall of said drum is also moved with said pilot valve so as to allow more fuel to escape as the suction in said air chamber increases as the air pressure falls.

6. A fuel injection system, a source of variable air pressure, a source of fuel under pressure, a metering pump comprising a cylindrical pump chamber, a fuel entrance thereto, a flanged plunger reciprocating therein, a loose piston spaced apart from said plunger and slidably mounted in and closely fitting said cylinder and engaged by said flange on the pumping stroke of said plunger, an element projecting laterally, from said plunger and located on the other side of said piston so as to engage therewith on the suction stroke of said plunger after a certain travel of said plunger, a discharge outlet delivering fuel to the source of variable air pressure, a relief port in said cylinder, a valve to close said Port and a projection from said plunger long enough to strike said valve so as to open said port when the plunger approaches the end of its pumping stroke and in which there is an escape port leading out of the discharge passage, a relief valve therein, means moveable in unison with said plunger to open and close said relief valve during the first portion of the injection period, means responsive to variable air pressure to vary this first portion of the injection period as the said pressure varies so as to increase the dicharge period with an increase in said air pressure.

GEORGE M. HOLLEY, Jn.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,597,787 Hausser et al Aug. 31, 1926 2,034,144 Lauret Mar. 17 1936 2,088,791 Huthsing Aug. 3,' 1937 2,136,636 Rotter Nov. l5, 1938 2,156,933 Alden May 2, 1939 2,310,370 Hoffer Feb. 9 1943 2,391,221 Been Dee. isf 1945 2,396,878 Plumb Mar. 19, 1946 2,413,115 Sheehan Dec. 24, 1946 2,418,412 Kucher Apr. 1 1947 2,445,266 High Ju1y 13j 194s 2,448,347 Beeh Aug. 31, 1948 2,453,329 Lee, II Nov. 9, 1948 2,474,396 Groves June 28, 1949 2,567,367 Deschamps Sept. 11, 1951 FOREIGN PATENTS Number Country Date 3,483 Great Britain 1880 

